[CentOS] postgrey, postfix, tld list

Hello all,

I am looking for the correct way to add postgrey to my system but 
whitelist everything except for com, org, and net domains.
Most of my spam is from .info domains.

There seems to be no way to only go after certain domains, instead 
postgrey wants to go after everything except what you whitelist.

So my idea was to whitelist .com, .net, .org, .gov, and a few others 
while greylisting the rest.
The syntax for the files want fqdn, email addresses, or domain names.
But How do you just add a .TLD?

postgrey_whitelist_clients  ??

*.com
*.net
*.org
??

this sound right?